The present invention relates to a dispenser for pasty compositions having a housing which contains a piston which can be displaced only in the emptying direction, the housing having an external handle for actuating a pump wall which wall can be pushed in the direction of the piston in order to dispense the contents of the dispenser from an outlet opening in a top cover of the housing, the cover being connected to the pump wall by a small tube.
A dispenser of this type is known from the Applicant's Federal Republic of Germany No. OS 34 16 999. In that publication the cover forms the actuating handle and, at the same time, the application surface which spreads the pasty composition for which purpose the cover is cupola-shaped. As a result of the pressure of the application the piston in each case lifts above the filling material column. This pulling up of the piston takes place with priority, i.e. before the remaining amount in the tube, which exerts a blocking action in the manner of a plug, could counteract the vacuum which is being created in the dispenser head. The pasty composition itself therefore, acts as and forms a valve.
Upon dispensing without utilization of the body-side contact pressure and therefore, for instance upon a depressing of the cover of the dispenser by hand, the hand of the operator may come into contact with the pasty composition. On the other hand, the outlet opening is in most cases rather small, so that the user may accidentally place his finger over it. The pressure which is then applied may lead to a spurting of the outward swelling contents of the dispenser, which, as a rule, results in a loss.